Echinopsis pachanoi( San Pedro Cactus), also known as Trichocereus pachanoi, is a fast-growing columnar cactus with green stems, occasionally.

Description

Echinopsis pachanoi is native to Ecuador and Peru. Its stems are light to dark green, sometimes glaucous, with a diameter of 6–15 cm (2.4–5.9 in) and usually 6–8 ribs. The areoles are space evenly along the ribs, approximately 2 cm (0.8 in) apart.

Echinopsis pachanoi is normally 3–6 m (10–20 ft) tall and has multiple branches, usually extending from the base but will emerge around broken branches. The tallest record specimen was 12.2 meters (40 ft) tall. White flowers are produce at the end of the stems; they open at night and last for about two days.

The flowers are large, around 19–24 cm (7.5–9.4 in) long with a diameter of up to 20 cm (7.9 in), and are highly fragrant. There are black hairs along the length of the thick base leading to the flower. 

Traditional uses

Echinopsis pachanoi has a long history of being use in the Andean traditional drugs. Archaeological studies have set up substantiation of use going back two thousand times, to Moche culture Nazca culture, and Chavín culture. Although Roman Catholic church authorities after the Spanish subjection tried to suppress its use, this fail, as shown by the Christian element in the common name” San Pedro cactus” – Saint Peter cactus.